Indiana Sen. Richard Lugar and former Georgia Sen. Sam Nunn stood on stage at the National Defense University as Panetta pinned small medals on their lapels.

“At the Pentagon, our primary mission is to keep this country safe. These two gentlemen have kept our country safe by virtue of what they've done. Their dedication, their leadership, their efforts at trying to ensure that we do everything we can to control the spread of weapons of mass destruction has been an incredible legacy of two individuals committed to trying to protect this world.”

The Cooperative Threat Reduction Program, established in 1991 as part of the Nunn-Lugar Act, is a critical part of the U.S. approach to reducing the threat of proliferation of weapons of mass destruction and related materials. It provided U.S. funding and expertise to help the former Soviet Union and other countries safeguard and dismantle stockpiles of nuclear, chemical and biological weapons, related materials and delivery systems.

The program also promotes collaboration with international and nongovernmental partners to advance regional engagement and multilateral cooperation.

“It is and will forever be the privilege of my lifetime to have been an eyewitness to the history that you two wrote and are still writing and that we honor today,” he told Lugar and Nunn.

Carter himself contributed to the U.S. understanding of what it would mean for the government of a superpower like the Soviet Union to disintegrate while it had nuclear weapons. He had just completed a study titled, “Soviet Nuclear Fission: Control of the Nuclear Arsenal in a Disintegrating Soviet Union.” And at a November 1991 meeting in Nunn’s office, according to moderator David Hoffman, Carter drove home to Nunn, Lugar and others at the meeting that the Soviet collapse was an immense security threat.

“As the Soviet Union disintegrated,” Carter said, “[Lugar and Nunn] realized before anyone else that the danger of a Soviet nuclear attack was being replaced by a new and unprecedented danger: the possibility that its nuclear arsenal might fall into entirely new and unaccustomed hands -- instantaneous proliferation on a massive scale, and worse and totally new, the specter of nukes falling into nonstate, even terrorist hands, events for which deterrence would not offer protection.”

Nunn and Lugar were right, the deputy secretary added, “and just as importantly, they were able to persuade the governments of the United States and Russia and all the successor states of the former Soviet Union to follow suit by making it physically and above all socially and politically possible for them to do the right thing, which was to reduce the nuclear threat.”

Because of the senators’ efforts, Carter said, Ukraine, Kazakhstan and Belarus all denuclearized. By the mid 1990s, all the former Soviet states became signatories to the Treaty on the Nonproliferation of Nuclear Weapons, and Russia was reducing and safeguarding the former Soviet Union’s nuclear arsenal.

Today, he explained, the Cooperative Threat Reduction Program is evolving in three ways. One is geographic expansion.

“The disaggregation and increasing sophistication of terrorist organizations coupled with leaps in technology that reduce the barriers to [weapons of mass destruction] acquisition,” Carter said, “has required the U.S. and our partners to increase the global reach of the program beyond the former Soviet Union, to close to 80 countries in all.”

Second, he said, the program has increased its emphasis on countering the threat of biological and chemical weapons.

“Countering these threats was always part of the Nunn-Lugar program, but scientific and technological advancements have made these weapons more dangerous and more widespread,” the deputy secretary said.

On the biosecurity front, the CTR program is partnering with foreign governments and international health organizations around the world to counter emerging threats, Carter said. One such partnership is the Richard Lugar Center for Public Health Research in Tbilisi, Georgia, which opened this year.

The facility is a regional biosurveillance hub, he said, that hosts Defense Department researchers from the Walter Reed National Military Medical Center, public health experts from the U.S. Centers for Disease Control and Prevention, and experts from Georgia's own health security agency.

“The center pursues three goals that are the foundation of CTR's biosecurity work around the world,” Carter said.

“The first is to improve information flow about disease outbreaks. We want a leg up in determining whether an outbreak is naturally occurring or manmade,” he said.

The second is to improve partner capacity, the human factor in biosecurity, the deputy secretary added, including better laboratory practices and systems to guard against insider threats.

The third is to keep the most dangerous pathogens on Earth consolidated and secured in a minimum number of well-guarded facilities.

“The biothreat spans the realms of national security and public health and the public and private sectors. CTR is trying to bridge these gaps as it looks forward, and the Lugar Center is a major step in that effort,” Carter said.

Another change in the Cooperative Threat Reduction Program has to do with the character and tenor of its interagency and international partnerships, he added.

“Here at home, we find that the increasing integration with other federal agencies is amplifying our threat-reduction efforts,” Carter said. “While we have worked closely with the departments of State and Energy … right from the beginning, we are tapping into valuable partnerships with agencies in nontraditional areas,” he said.

“The [CDC] and the [Agriculture Department’s] Foreign Agricultural Service, for example, have unique health engagement relationships that the CTR program is relying on to secure biological facilities and increased biosurveillance of especially dangerous pathogens,” such as anthrax, the deputy secretary added.

Overseas, he said, the Cooperative Threat Reduction Program emphasizes the importance of putting threat reduction into the hands of frontline international partners. “By building the capacity of other responsible nations, we are increasing their security and minimizing the likelihood that threats materialize across borders, including in the United States,” he added.

Carter said the work of the two senators will endure through future generations. “CTR will forever be a part of human governance because we can never forget what we know about these destructive weapons,” he said, “and it will forever be associated with two names: Nunn and Lugar.

Later, as Panetta prepared to present the awards, he said it was his privilege to recognize the legacy of both men, calling their leadership “a symbol of the kind of public service that is so important to our country, now and in the future.”

The secretary added that his biggest national security concern today “is whether or not those who are elected to office have the will and courage to be able to govern this country and to be able to find the answers to the problems that confront us.”

Lugar and Nunn, Panetta added, “have spent their lives working to solve problems, to govern this country and therefore to do everything in their power to make our democracy work better and keep this country safer.”